Duplicate titles under facet

[buckle2000]

The example and schema are here

Note in the screenshot below, each column/row has its own title. I think each row should share one title.

{
  data: {values: data},
  facet: {column: {field: 'i', title: 'arm', type: 'ordinal'}},
  width,
  spec: {    
    vconcat: [{
      title: 'Expectations',
      layer: [{
        width: 180,
        mark: 'area',
        encoding: {
          x: {field:'x', title: 'proportion'},
          y: {field:'y', title: 'probability density'},
          opacity: {value:0.1},
        },
      }, {
        mark: 'rule',
        encoding: {
          x: {field: 'p'},
        },
      }]
    }, {
      title: 'Outcomes',
      mark: 'bar',
      encoding: {
        x: {field:'name', type:'nominal', title:null},
        y: {field:'count', type:'quantitative'},
      }
    }]
  }
}

P.S. I also ran into #4680 and #5219 in that working example

[domoritz]

This is expected behavior since the title is set for each layered chart.

[buckle2000]

How can I set title for each row then? As in #4680? I might try to fix that myself.

[domoritz]

I'm not sure I understand. Can you be specific about what you want? A sketch would help me answer your question.

[buckle2000]

Sorry for being unclear. I meant using a spec like concat: [facet: {title: ...}, facet, {title: ...}] to only show one title for each row. However, a specification like that will error out (as in #4680 and here).

[domoritz]

Ahh, I see. Can you create a minimal example that reproduces the problem in the editor?

[buckle2000]

If you mean the problem of duplicate titles, here's an example in the editor.

[domoritz]

The repeated titles are expected behavior. The spec is asking for a repeat inside a facet. The individual views do not have access to their parents and therefore the titles need to be repeated. Also note that we do not yet officially support repeat inside facet.

If you want a single title per row, use vconcat with facet.

https://vega.github.io/editor/#/url/vega-lite/N4KABGBEAkDODGALApgWwIaQFxUQFzwAdYsB6UgN2QHN0A6agSz0QFcAjOxge1IRQyUa6ALQAbZskoAWOgCtY3AHaQANOCgATZAgBOjQnh4qckAKIAPdKkJjkYAGbddYfERLkmLDnXjdUQrSBohJ4UoywsKw6pACs0gDMAExqGpCa6HiYOMCQFOhi0bDYYADaudlQAIJqUOwlSQAcAL6qYBUlkABCtZD1OLGxzQC6rWkUfkrwmSWlGhCgEEtQRnh2nQAqzHaOzo6MurB4YLrcAO6pyxCQDujwyHgluQ6MyGKanZhtkHgAnoTITrOTSMJQFSBjK5QWAA+BPSAYXQAa067HQugh8zAkKWiyuP22gNMWzW9icLlgyEmmhO50u+Nu90eORur3en16fwBQN0ILBYgh6ihkBhVPhiJRpjRGOaWNlEGGIGaQA

I hope that help.

[buckle2000]

Thanks, but facet inside vconcat is broken (editor link). Can you point me towards fixing this?

[domoritz]

Ahh, that's a bug. I filed this as a new issue at #5475. Thanks for the small example!